Within the Internet today, packets of data are routed between sources and destinations over a plurality of large, nationwide networks whose operating entities are typically referred to as National Internet Service Providers or NSPs. An NSP is an Internet Service Provider (ISP) which has a nationwide network of DS3 capacity of 44.736 Megabits per second (Mbps) or higher, and is present at a minimum of five public NAPs. NAP stands for Network Access Point. There are at least 15-20 such nationwide networks in the United States (U.S.) at the present time, many of which are owned and operated by large telephone companies. Some representative NSPs are MCI, Sprint, WorldCom/UUNet, ANS, AGIS, Netcom and PSI.
In the pre-commercial days of the Internet, there was one NSP, the US National Science Foundation (NSF), which ran a nationwide network infrastructure known as the NSFNet. If two end-users wanted to communicate with one another, they had to connect either directly or indirectly (via a smaller regional ISP) to the NSFNet. Over time, a small number of commercial entities evolved to create their own nationwide network infrastructures which provided the same services as the NSFNet, but for the commercial sector. When the NSF decided to decommission the NSFNet and thereby commercialize the entire Internet, it was anticipated that there would evolve an even larger number of commercial nationwide network infrastructures which would become the Internet connectivity points, either directly or indirectly (via a smaller regional ISP), for all end-users. Two end-users connected via the same national infrastructure would communicate with one another over that infrastructure, but a method was needed to allow for the exchange of traffic between the various national infrastructures so end-users on different infrastructures could communicate with one another. This problem was solved by the creation of several Network Access Points or NAPs.
A public NAP is a public infrastructure operated by private entities (NAP operators) which creates a neutral meeting place for the exchange of TCP/IP packet traffic between any two entities connected to the NAP, provided the entities have an agreement in place to exchange traffic (known as a peering agreement). Today, there are five major NAPs located in the U.S. Two are located in the San Francisco Bay area, one in Washington, D.C., one in New York, and one in Chicago. The NAP operator is paid a fee by any entity connecting to the NAP, and the peering agreements between entities outline the strategy for cost-recovery of their traffic exchange (if any).
Although the NAP architecture seemed sound when it was first developed, time has shown that it has failed to scale with the growth of the Internet. There are a number of reasons for this. First, because the Internet routing protocol used among entities at a NAP (Border Gateway Protocol version 4, or BGP4) does not have hooks to allow for automated, even traffic distribution across NAPs, most of the world's exchanged traffic occurs at a small number of the total number of NAPs because the NAPs which are used must be manually configured by each provider. The result of this is that those NAPs which are taking most of the traffic are overloaded and packets going through them are being dropped. It should be noted that the Transmission Control Protocol/Internet Protocol (TCP/IP) can gracefully recover from a dropped packet because of its Acknowledgement scheme, but this greatly increases the time it takes for information to be exchanged between two end-users, thus causing performance problems for the users. Second, the lack of quick technical advances in Local Area Network/Metropolitan Area Network (LAN/MAN) technologies have made the NAP scaling problems worse. Asynchronous Transfer Mode (ATM) and its promise of high bandwidth is unsuitable for TCP/IP traffic. FDDI (Fiber Distributed Data Interface, operating at 100 Mbps) the only current, stable LAN technology today, is not enough bandwidth to handle traffic levels in the current model. Finally, because the NAP infrastructures are managed by the NAP operators and connections into the NAPs are managed by the connecting entities themselves, there is a continual discontinuity between the available bandwidth within the NAP infrastructure and the amount of bandwidth the entities put into the NAP, thus causing more packet loss.
Thus, there exists a need for a way to bypass the NAPs whenever possible by creating a new interconnection model managing the routing of TCP/IP traffic between the NSPs and users.